"The work they are doing is absolutely crazy. The whole thing is exceedingly dangerous," said Lord May, former President of the Royal Society and one time chief science adviser to the UK government, in an interview with The Guardian's Ian Sample. "Yes, there is a danger, but it's not arising form the viruses out there in the animals, it's arising from the labs of grossly ambitious people."

Supporters of so-called "dual-use" research like Kawaoka's argue that his team's work is vital, because it allows scientists to get a head start on understanding viruses that might one day pose a serious risk to the global population. On the other hand, there are many (like May) who fear that findings from such research could be deadly were a virus like Kawaoka's to escape accidentally, or find its way into malevolent hands.

More on the scientific community's reaction to Kawaoka's virus at The Guardian.